Horspower v Gearing

To all those out there a little humbled by the big litre sportsbike consider this.A vfr in 6th gear does about 4450 at 100km/h or 62mph.A tlr does about 3600rpm a Hyabusa does about 3400 and a gsxr1000 does about 3900-4000.Because of the vfr,s shorter gearing(even better with 1 tooth less on the front) its performance isn,t as far behind as hp and torque figures suggest.The shorter gearing with a 12500rpm cutout enable it to use a shorter gear at the same road speed ,matching the bigger bikes(except the gsx-r 1000 with an 11000rpm limit).Don,t believe me? When i had 110hp at the tyre on a ride day i exited a corner at the same speed as a tlr with yoshi pipes and slicks with approx 122 hp at the tyre and past him by the end of the straight.Yesterday in a top gear rollon with a hyabusa with 160hp at the tyre from 150-220kmh up a hill it was dead even.I now have 116 at the tyre and 150km/h equals about 6500rpm, right where it goes hard from.If this roll had of started at 110-120km/hr the busa would have pulled about 500metres on me as I,m out of the power band,but by using 4th gear it would have only walked away.Trust me guys,keep it over 6500 and they won,t dissapear.

 

One should keep in mind that the less the cc's the higher the revs at the same speed as more cc's bikes. So in fact a 800 will cruise at least 1000rpm's higher than 1000+cc bikes, which is how it is was build rpm vs speed. But the V-four engine is in fact a very high reving engine unlike the V-twins which have more low rev torcue but not capable to rev to 12000rpm like the VFR. On pull away the VFR will easily stay close or even outperform many bigger bore bikes. 0-100km/h on VFR is 3.0 sec, a Blackbird does it in 2.8 sec. Not a big difference in real life taking the cc difference in account. It's only from around 180km/h that the bigger bikes will slowly drift off. Hard riding in corners is a breeze with the 800, all depending on the rider. It's easy to go 300 on a Busa/ Bird/ ZX12 on a straight, but at cornering they cannot outperform the VFR easily. An experienced rider on the 800 will easily outperform the bigger bikes in heavy corners. So what, if I wanted to go 300km/h I would not be riding a VFR800!!!
Be patient, a more cc vfr will see the light one day...

 

Speaking Of Blackbirds I,ve been to 2 drag nights and seen blackbirds not able to break 11.1 seconds.After only 2 nights I got down to 11.3,before the gearbox broke 3rd gear.2 months later honda tells me its on vendor back order.This means the gear that broke the dogs off it is a special outside manufactured part.It is darker than the other gears so is tempered differently too.This is frustrating as the busa,s in aust are mostly doing high 10,s to low 11,s so I,m still in the hunt.

 

Hey Isaac, what year model is your machine? and what did you do to tweak it? iI have a stock 02' Vfr and am looking for a few ideas.

 

I would like to know what year, etc. So far the mods that I have planned are a new set of pipes, staintunes, PCIII usb, K&N ZG double bubble, and to mess with my buddies that friends of mine that have liter bikes, dropping one tooth on the front sprocket for harder acceleration.
I have been told that with the pipe and PC mods, I should be in the 115Hp range. With a tooth lower front sprocket, it should really help with acceleration.

 

I've never heard such a bunch of crap in my life. A stock BUSA will smoke a VFR in any type of roll on. These 1/4 mi times are also from people scared to modulate the clutch on a bigger bike which is what it takes to get them in the low 10s or high 9s. A BUSA out of the box will run a low 10 without a pro rider provided you know what you are doing I've seen good riders get these bikes into the 9s stock by just lowering the front end. Also 2/10ths in 0-60 is bike lengths and it just keeps on pulling away. The bikes you are talking about all put out over 150hp at the wheel and weigh almost the same as a VFR which stock is only putting on 100hp and in a straight line they will simply pull away. As far as cornering is concerned the VFR may have a slight advantage as the big sportbikes are meant to go in a straight line. I have yet to see a dyno sheet where a VFR puts out more the 107hp unless it has a big bore kit and there isn't one made for a VTEC there is no way one is putting out 115hp at the wheel with a pipe and a PC. I have owned two VFRs and ridden at least half a dozen of them not a single one will keep up with any of the bikes mentioned except for maybe a TLR, but that all depends who's riding it. I actually beat one on my VFR from a dead stop up to 110mph where I let off but that was mainly because the kid couldn't ride it. Granted shorter gearing will give you quicker accerleration and is a great mod for a VFR it will not make up a 40hp and 40lb torque variance. I love the VFR and always will but don't make into something which it is not and that's a liter+ sportbike.

 

Wow, talk about a killjoy. I was just quoting numbers that other VFR owners had given me with those mods. All I was doing was looking for a few ideas, not a huge post about how we are all full of crap.

 

I call it like I see it and my reply was meant for Mr. I can hang with a BUSA on my VFR which is complete nonsense. If you want to improve the performance of your VFR get a pipe a PC and change the sprocket. If you're ready for a chain do a 520 conversion and your acceleration will be even better as the rotating mass will be lighter. Not trying to be a killjoy as you say it but don't expect 115hp at the wheel from a pipe an PC. That's a 15% increase and it's just not going to happen. Any good mechanic will tell you 7 to 8% tops with a good map. I've ridden a VTEC before and after with mods you describe and you'll be pleased. Get the Staintunes they are the best pipes for the VFR out and sound great with the baffles removed.

 

I can agree with not hanging with a busa, especially in a straight line. I have been around a lot of guys that ride them though, and get them in the corners, and they can't hang, at least in my personal experience. Most of the guys that I see with them, they have the extended swingarms, etc. etc. and they just can't corner.
I am actually looking to the Laser Xtreme pipes. I really like the sound, and they look awesome. I figure with the PC and the new front sprocket, I will at least be able to hang a little closer to my buddies with liter bikes,

On a different note, how do you like your RC51? I have been thinking of adding one of them as a second bike for my garage, especially when I just want to take a ride by myself.

 

I love my RC. I was looking to go sportier then my VFR and always loved the RC just like twins when I saw it in black I had to have it. It can be a little uncomfortable on long rides but with an aftermarket seat not so bad good enough that I got rid of my VFR. It sounds great with pipes, handles great and has a really linear power curve. I thought it would be a wheelie machine like most litre bikes but the front end stays down you can really put the power down early. I have friends with R1 and GSXR 1000s who just can't get on the power like I can. It's heavier and dated compared to most new sportbikes out there but it's a feather compared to a VFR. Plus it's different and loud which I like. Tons of aftermarket parts so you can go crazy and they hold their value pretty well like most hondas. I'm keeping this one and may add an ST1300 to my garage at some point for the long hauls.

I think the laser pipes look cool never heard them though. I'd seriously consider the 520 conversion when you need a chain and don't forget the sprocket will screw up your speedo.

 

Two Questions based on info on this thread (04 VFR)

Hey RC51, I agree with you on the bigger bore bikes on power. I have an 04 vfr with filter and Staintune exhaust, going to PC and map the bike this winter... Two questions for you since you seem to know the vfr pretty well. First if you go down a tooth upfront would you change rear sprocket as well??? Second when I installed the Staintune it was a sealed can so did not see a way to remove baffle without major reconstruction, did I miss something or do you need to tear it apart and re-weld???

Thanks

 

No you don't need to change the rear sprocket when you do the front but if your chain is near replacing i'd do everything at once and do a 520 conversion. Also remember your speedo will be off. If you have low miles on your bike or a new chain i'd just do the front. Staintunes come with a street baffle it should be easy to remove your pipes should have came with instructions. I have not owned a VTEC VFR but my buddy bought staintunes for his 03 I heard them with the baffle and without he said it was easy to remove it fits right into the back of the pipe with a phillips head screw. Perhaps you don't have one.

http://www.staintune.com.au/faq4.htm

 

RC thanks

Hey, got the baffles out they had the hex screws positioned on the inside kind of under the rear faring (I must have missed on install). Sounds a lot better without the baffles... I bought the bike as a left over so it only has like 5k miles (especially since I broke my hand in the summer which took some riding time away).... Thanks for the advice...

 

laser

iv got a o2 vtec with laser deep tone full system on it and a pc111 and i own a 1990 vfr fl and i hope you have as much fun on yours as i have over the years and as all my mate have the 600 sports (gsxr / zx636r /zx6rr / zx6r / cbr6rr / sv650) a good lot to go out with and ill keep up with any of them at any speed and ride harder and longer than all of them think than you cant go wrong with a vfr and the tone i get out of the back of my bike sets me apart from all of them

good riding mate

 

...well all I have to say is ...took my 97 out yesterday and took one of my local highways at 125 mpr and thats plenty fast for me ...springs comming boys and girls ...

 

furthermore ...whos gives a rats ass bout some busa , gxer ...VFR the SWISS ARMY KNIFE of motorcycling rules the road in my book ..period ..

 

Swiss Army Knife eh, yah I can see that and I heartily agree!

I installed a Vortex 520 conversion on my 91 last summer and it was a nice kit. I especially liked the machined aluminum rear sprocket with the gold chain. It did result in a noticable change in the accelleration of the bike and it would loft the front wheel in second gear if provoked which was cool. However it also had a down side! Besides the resultant speedo error which was a PITA, it also meant that the engine was screaming when you were cruising at 80 MPH on the highway. I lasted a week before ordering a stock sized front sprocket. I left the rear one tooth up and it was just fine for general use and the track as well. I will try to upload a pic of the installation as it looked sweet.

 

You say screaming at 80, what kind of rpm? Also how much variance on the speedo and at what speeds? Appreciate your input, I'm due for new sprockets, chain, and pipe myself.

 

The problem is that the relationship between the tach and the speedo stays the same regardless of the sprocket you have installed because the speedo picks up it speed signal off the countershaft. It was last summer so I can't recall the exact rpm I was doing but it was something like 1000 higher that it was with the stock gearing (around 5500 I think). I had to use someone elses to tell me how fast I was going because the speedo error was over ten MPH.

 

This is true only on analog models if you have a digital speedo 02 and later gearing changes will alter you readings this why they sell recalibration units for it.